The present invention relates to container assemblies used for the storage, handling, transport, and dispensing of liquid chemicals. In particular, the invention relates to a container assembly, which utilizes a film pouch located within a bottle, container, or over pack and is used in conjunction with dispensing systems for the distribution of semiconductor processing liquid chemicals in a manufacturing process.
Presently the users of liquid chemicals have a limited choice of packaging, handling, delivery, and disposal methods for such materials such as acids, solvents, bases, photoresist, dopants, inorganics, organics, biological solutions, pharmaceuticals, and radioactive chemicals. One prior art system delivers chemicals from a bulk source, usually a 55-gallon drum, to the point of use. Usually these systems include the drums, piping, and automated delivery equipment, which makes such systems very expensive to use. As a result only a small amount of manufacturers, who have sufficient volumes to offset the equipment costs, use these systems.
Another widely used alternative is to handle the liquid chemicals in bottles made of glass or polyethylene. This method has several disadvantages. In particular, glass and polyethylene have been shown to contribute particulate contamination and metal-ion extractables, which significantly compromise the desired purity level of liquid chemicals. In addition, the dispensing methods used with glass and polyethylene bottles also compromise the purity of the chemical contents. Manual decanting exposes chemicals to atmospheric contamination, and also can compromise the safety of the technicians handling the bottles. With glass bottles there is the added danger of breakage with even the slightest abuse in handling. Disposal of empty bottles also becomes a concern. Sanitary disposal typically requires rinsing, tagging and crushing the used bottles. This process is quite expensive and may become an environmental concern.
Another alternative is the use of blow-molded fluoropolymer bottles. Manual handling of the bottle is maintained (as opposed to bulk delivery), yet the fluoropolymer bottle provides inertness, which is helpful to maintaining the purity of the chemicals being handled. Blow molded bottles can be expensive and usually are cost justified by use of a return program, however a returnable program presents numerous logistical problems for suppliers and users alike.
A final alternative is a bag in the bottle method in which a bag (or pouch) is inserted in a bottle (or container) and the fluid is extracted via a probe. A pressure is inserted between the bag and the bottle and forces the liquid out of the bag to a reservoir, which is connected to a pump. This method has its shortcomings in that a significant amount of fluid quite often resides in the bag after effective usage (e.g., liquid suction is lost allowing a residual amount of fluid to remain in the bag). In most cases the loss of this residual fluid is not significant, however, if the fluid involved is expensive or has a potential impact on the environment, then recovery of the residual fluid becomes advantageous (an exemplary type of fluid is photoresist). Consequently there is a continuing need for improved containers and storage systems, which allow the maximum amount of residual fluids to be extracted as possible.
The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is intended to neither identify key or critical elements of the invention nor delineate the scope of the invention. Its primary purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
The present invention is a container assembly for liquids, which comprises a pouch wherein liquid is stored, filled or emptied. The assembly further comprises an outer container, bottle or over pack that surrounds the pouch and a retaining means for engagement of the pouch to the outer container. The geometric shapes of the pouch, or the outer container, or a combination of both the pouch and the outer container are such that they facilitate the extraction process, thus ensuring that the maximum amount of residual fluids are utilized preventing excessive costs and environmental waste. For example, a bottom portion of the pouch is sloped toward a collection reservoir in the pouch, for example, in the middle thereof. Consequently, the photoresist material within the pouch is directed into the collection reservoir portion, wherein a liquid extraction member is located to remove photoresist therefrom.
According to one aspect of the invention, a semiconductor processing liquid containment assembly comprises a container and a pouch residing therein. The assembly also comprises a liquid extraction member that extends into the pouch for the removal of semiconductor processing liquid therefrom. The pouch or container (or both) have a bottom portion associated therewith that is configured to direct liquid within the pouch to a collection region associated therewith. The liquid extraction member extends into the collection region and is operable to extract the liquid therefrom. Due to the bottom configuration of the pouch and/or container the liquid within the pouch is directed into the collection region, thereby facilitating an efficient removal of liquid therefrom and reducing an amount of waste fluid remaining therein.
To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects and implementations of the invention. These are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.